*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body{
    width: 100%;
    background-color: #f2f2f2;
}
.leftbox{
    position: relative;
    width: 100%;
    height: 50px;
    background-color: #fff;
    box-shadow: 0 1px 2px rgba(0,0,0, .1);
}
.leftbox input{
    display: none;
}
.leftbox label{
    position:absolute;
    top: 10px;
    left: 240px;
    color: #666;
    padding-left: 20px;
    cursor: pointer;
    transition: all .5s;
}
.leftbox ul {
    position: absolute;
    top:0;
    left: 0;
    width: 240px;
    height: 180vh;
    background-color: #050f35;
    transition: all .5s;
}
.leftbox ul li{
    width: 100%;
    height: 70px;
    margin-bottom: 10px;
    list-style: none;
}

.leftbox ul li:first-child{
    display: flex;
    align-items: center;
    margin-top: 40px;
}
.leftbox ul li:first-child img{
    height: 50px;
    width: 50px;
    border-radius: 50%;
    margin: 0 25px;
}
.leftbox ul li:first-child span{
    color: #fff;
    font-size: 16px;
    white-space: nowrap;
}

.leftbox ul li a{
    display: flex;
    align-items: center;
    height: 100%;
    width: 100%;
    color: #d2d2d2;
    text-decoration: none;
    transition: all .5s;
}
.leftbox ul li img{
    width: 20px;
    height: 20px;
    margin: 0 25px;
}
.leftbox ul li a span{
    font-size: 14px;
}
.leftbox ul li a:hover{
    color: #fff;
    background-color: aquamarine;
}
.leftbox input:checked + label{
    left: 0;
}
.leftbox input:checked~ul{
  left:-240px ;
}

.cen{
    position:relative;
    flex: auto;
    margin-left:50%;
    margin-top: 20px;
    margin-bottom: auto;
}
.wangzhan{
    position:relative;
    flex: auto;
    margin-left:30%;
    margin-bottom: auto;
}